1. Field of the Invention
This invention relates to a new endless power transmission belt construction and to a new method of making an endless power transmission belt construction.
2. Prior Art Statement
It is known to provide an endless power transmission belt construction having opposed side edge means and having an inner surface means defining a plurality of longitudinally disposed and alternately spaced apart projections and grooves for meshing with a ribbed surface means of a rotatable pulley means or the like and defining a plurality of transversely disposed and alternately spaced apart projections and grooves. For example, see the U.S. patent to Hull, U.S. Pat. No. 4,647,278.
It is also known to provide alternately spaced apart projections and grooves in an endless power transmission belt construction wherein the longitudinal spacings between the transverse grooves or/and the depths of the transverse grooves are staggered so as to tend to reduce noise during normal operation of the belt construction. For example, see the U.S. patent to Imamura, U.S. Pat. No. 4,264,314.
It is also known to provide vehicle tires with treads and building ceilings with notches that respectively have spacings or depths that are staggered on the basis of a quadratic residue sequence based on a prime number. For example, see the article in Science News, Vol. 129, Jan. 4, 1986, pages 12-13, entitled "Acoustic Residues."